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PubMed2026

Celery seed extract attenuates sarcopenic obesity and age-related sarcopenia by reducing intramuscular lipid accumulation in mice.

BACKGROUND & AIMS: Sarcopenia is characterized by progressive loss of skeletal muscle mass and function and is increasingly recognized to be influenced by metabolic disturbances associated with aging and obesity. Intramuscular lipid accumulation has emerged as a key pathological feature linking metabolic dysfunction to skeletal muscle deterioration. Celery seed extract (CSE) possesses anti-obesity, anti-inflammatory, and antioxidant properties; however, its potential role in skeletal muscle metabolism has not been well investigated. This study aimed to determine whether CSE attenuates skeletal muscle deterioration associated with obesity and aging through modulation of intramuscular lipid accumulation and related metabolic pathways. METHODS: Diet-induced obese mice and naturally aged mice were used to evaluate the effects of CSE supplementation. Skeletal muscle mass, grip strength, muscle morphology, intramuscular lipid content, mitochondrial metabolic signaling, inflammatory responses, and muscle protein turnover pathways were assessed using biochemical, molecular, and histological analyses. RESULTS: CSE supplementation significantly improved skeletal muscle mass, grip strength, and muscle fiber cross-sectional area in both obese and aged mice. These improvements were accompanied by reduced intramuscular triglyceride and cholesterol accumulation. Mechanistically, CSE improved mitochondrial metabolic signaling by activating the AMPK-PGC-1α pathway and increasing mitochondrial oxidative phosphorylation proteins. In addition, CSE suppressed inflammatory signaling pathways, including MAPK activation and NLRP3 inflammasome signaling, and improved muscle proteostasis by enhancing myogenic regulators while reducing the expression of proteolytic factors such as MuRF1, Atrogin-1, and myostatin. Correlation analyses further indicated that intramuscular lipid accumulation was closely associated with mitochondrial dysfunction, inflammatory activation, and muscle atrophy. CONCLUSIONS: These findings demonstrate that CSE alleviates skeletal muscle deterioration in both obesity- and aging-associated sarcopenia by reducing intramuscular lipid accumulation and improving mitochondrial metabolism, inflammatory responses, and muscle protein turnover. Targeting intramuscular lipid accumulation may therefore represent a promising nutritional strategy for preventing sarcopenia associated with metabolic and aging-related stress.

AMPK–PGC-1α↗

PubMed2026

Effects of Adding Incentive Spirometry to Hospital-Based Cardiovascular Rehabilitation on Pulmonary Complications, Hospital Length of Stay, and Clinical-Functional Recovery After Cardiac Surgery: A Randomized Controlled Trial.

BACKGROUND AND PURPOSE: This study investigated the effects of combining incentive spirometry with cardiac rehabilitation compared with cardiac rehabilitation alone on postoperative pulmonary complications, clinical-functional recovery, and hospital length of stay in patients undergoing cardiac surgery. METHODS: Randomized controlled trial was conducted from May 2019 to October 2023 in two hospitals, including 46 inpatients undergoing cardiac surgery. Participants were assigned to incentive spirometry plus cardiac rehabilitation or cardiac rehabilitation alone. Both interventions were performed twice daily; spirometry used a volume-oriented device, and rehabilitation followed a seven-step protocol (2-4 METs). Outcomes included postoperative pulmonary complications, functional capacity (6-min walk test), handgrip strength, respiratory muscle function, and length of hospital stay. RESULTS: The incentive spirometry associated with cardiac rehabilitation group had a longer extracorporeal circulation time (98 ± 26 min) than the cardiac rehabilitation group (76 ± 1; p = 0.008). Both groups showed a postoperative decline in respiratory muscle strength, and walking distance (MD: -64.37 m; 95% CI: [-24.1; -104.6]; d = 0.71), with no difference in postoperative pulmonary complications and handgrip strength. The incentive spirometry associated with cardiac rehabilitation group did not significantly differ on postoperative hospital stay compared with the cardiac rehabilitation group (MD: -1 day; 95% CI: [-4.71; 2.71]; d = -0.19). CONCLUSIONS: In this study, no additional benefit was observed with the addition of incentive spirometry to cardiac rehabilitation compared with cardiac rehabilitation alone. No significant differences were detected between groups in postoperative pulmonary complications, hospital length of stay, or clinical-functional recovery among individuals undergoing cardiac surgery. TRIAL REGISTRATION: Brazilian Registry of Clinical Trials (REBEC) under the number RBR-8tsjf97.

Aged↗

PubMed2026

Metabolic pathways linked to sarcopenia in the Bushehr Elderly Health Program: kynurenine, nicotinamide, B-vitamins, and sulfur amino acids.

BACKGROUND: Sarcopenia, characterized by the loss of muscle mass and function, is a common condition in the elderly, associated with increased morbidity and mortality. Metabolic pathways, including the kynurenine, nicotinamide, B-vitamins, and sulfur amino acid pathways, may play a significant role in the development and progression of sarcopenia. This study investigates the relationship between metabolic pathways and sarcopenia, aiming to identify potential therapeutic targets. METHOD: Four hundred participants over 60 years were randomly selected from the second stage of the Bushehr Elderly Health Program (BEH). Frozen plasma samples were used to measure metabolomics. We used factor analysis and logistic regression analysis to determine the kynurenine-tryptophan metabolites associated with sarcopenia and its components. RESULT: Study participants included 89 sarcopenic subjects aged 72.92 ± 7.32 years and 307 non-sarcopenic subjects aged 68.12 ± 5.56 years. In full model adjustment, factor 3, which included methionine, tryptophan, 3-hydroxyanthranilic acid, picolinic acid, and xanthurenic acid, was associated with 38.3% lower risk of sarcopenia (OR = 0.617 [95%CI = 0.436–0.875]); Factor 6, which included methylmalonic acid and total homocysteine, was associated with a 33.7% increased risk of sarcopenia (OR = 1.337 [95%CI = 1.031–1.735]); and factor 7, consisting of nicotinamide, were related to a 25.2% lower risk of developing sarcopenia (OR = 0.748 [95%CI = 0.571–0.979]). Additionally, factor 1, which included quinolinic acid, kynurenine, 3-hydroxykynurenine, neopterin, kynurenic acid, anthranilic acid, cystathionine, and total cysteine, was linked to a 49.2% higher risk of low muscle strength, while factors 3 and 7 were associated with approximately a 24% decrease in risk of low muscle strength. Factors 5, consisting of serine and glycine, and factor 7 were related to 43% and 27.7% lower risk of low skeletal muscle index, respectively. While factor 6 was related to a 32.8% higher risk of low skeletal muscle index. Factor 1 was also related to a 32.9% higher risk of low walking speed, while factor 3 was related to a 28.5% lower risk of low walking speed. CONCLUSION: Specific metabolites from the kynurenine, nicotinamide, B-vitamin, and sulfur amino acid pathways are significantly associated with sarcopenia and its key parameters, such as muscle strength, skeletal muscle index, and walking speed. These findings suggest that metabolic profiling could offer valuable insights for early detection and targeted interventions for sarcopenia in elderly populations.

Humans↗

PubMed1976

Respiratory mechanics in airways obstruction associated with inspiratory dyspnoea.

Inspiratory muscle strength and the flow and elastic pressure opposing inspiration were measured in seven patients with severe airways obstruction who found inspiration difficult at rest. A comparison was made of measurements obtained from seven normal subjects and five patients with airways obstruction not experiencing inspiratory dyspnoea at rest. Measurements were also obtained when inspiratory dyspnoea was induced in the normal subjects by adding an inspiratory resistance or by voluntarily increasing lung volume. Compared with the controls the inspiratory muscle strength of the patients was reduced but was not significantly less than that of the patients without inspiratory dyspnoea. The pressure required to produce inspiratory flow was significantly greater when inspiratory dyspnoea was present (P = 0-01). However, there was considerable overlap in the pressures of those with and without inspiratory dyspnoea. A better relationship was obtained when muscle strength was considered. The ratio of inspiratory muscle strength to the pressure required to produce flow was 0-24 +/- 0-07 (mean +/- SD) in patient with inspiratory dyspnoea, 0-10 +/- 0-03 in patients without inspiratory dyspnoea, and 0-033 +/- 0-019 in normal subjects. There was no overlap between the two patient groups. The ratios of the normal subjects were increased when inspiratory dyspnoea was induced and, with the exception of two cases, were all above those obtained when inspiratory dyspnoea was absent. Inspiratory dyspnoea was experienced with lower ratios in the normals than in the patients with airways obstruction.

Airway Obstruction↗

PubMed2026

Therapeutic Exercise Protocol During Hospitalization in Pediatric Oncohematological Patients: Randomized Clinical Trial.

BACKGROUND: Leukemias, lymphomas, and central nervous system tumors are among the most common pediatric cancers and may lead to motor deficits, impaired balance, reduced muscle strength, fatigue, and decreased functional capacity. Early physiotherapy during hospitalization may help prevent inactivity and support functional preservation in this population. OBJECTIVE: To evaluate the effects of a therapeutic exercise program on quality of life, muscle strength, fatigue, and functional capacity in hospitalized pediatric oncohematological patients. METHODS: Thirty participants aged 8-17 years with oncohematological diseases were randomized to an intervention group (IG) or a minimal active physiotherapy comparator group (CG). Assessments included the 6-min walk test, handgrip dynamometry, the PedsQL Multidimensional Fatigue Scale, and the PedsQL Cancer Module at admission and discharge. The IG performed daily 25-min supervised sessions including aerobic, resistance, and breathing exercises with ambulation guidance, whereas the CG received breathing exercises and ambulation guidance. RESULTS: No significant group × time interactions were observed for total fatigue or its domains, overall quality of life or its assessed domains, handgrip strength, or six-minute walk test distance. Time-related changes were observed for some outcomes, but these occurred without evidence of differential change between groups and were not interpreted as effects of the structured exercise protocol. No intervention-related adverse events requiring permanent protocol discontinuation were recorded. CONCLUSION: The structured in-hospital therapeutic exercise protocol could be delivered under close clinical supervision without recorded intervention-related adverse events requiring permanent discontinuation. However, the structured protocol did not demonstrate superiority over the minimal active physiotherapy comparator for fatigue, quality of life, muscle strength, or functional capacity. These findings should be interpreted cautiously because of the small sample size, clinical heterogeneity, variable intervention exposure, and limited intervention-fidelity data. TRIAL REGISTRATION: Brazilian Registry of Clinical Trials (ReBEC), RBR-8sxnfyd.

Humans↗

PubMedDate not supplied

Preservation of bulk and strength in muscles affected by neurogenic lesions.

Mechanisms involved in maintaining bulk and strength in partially denervated muscles of patients with neurogenic lesions are discussed. Estimation of muscle fiber hypertrophy by electrophysiological examination is possible, but it depends on the construction of sampling electrodes with precise geometry. The arrangement of muscle fibers of motor units within the muscle is discussed by analogy with the four-color map problem. An experiment to measure the twitch tensions of individual motor units in man is devised; it requires the use of microprocessor control of the stimulus and recurrent measurements of the twitch forces.

Animals↗

PubMed2026

Effects of blood flow restriction training combined with resistance training on lower-limb strength and sport-specific performance in athletes: a systematic review and meta-analysis.

BACKGROUND: In contemporary sports science, athletes and coaches continuously explore strategies to reduce training load and injury risk while increasing muscular strength and sport-specific performance. This meta-analysis evaluated the effects of blood flow restriction training (BFRT) combined with resistance training (RT) on lower-limb muscle strength and sport-specific performance in athletes. METHODS: Relevant randomized controlled trials (RCTs) were systematically searched across major databases (e.g. PubMed, Web of Science, Cochrane, CNKI, Wanfang Data, and Embase) from inception until November 2024. Two independent reviewers carefully assessed the studies. Data analysis was carried out using RevMan 5.4 software, which included heterogeneity testing, meta-analysis, subgroup analysis, and assessment of publication bias. RESULTS: Ten RCTs (181 athletes; 91 in the BFRT and RT group, 90 in the control group) were included. Outcomes determined BFRT combined with RT yielded notable enhancements in lower-limb muscle strength (SMD = 1.09, 95% CI [0.52, 1.66], p < 0.05) and muscle hypertrophy (MD = 1.09, 95% CI [0.10, 2.09], p < 0.05) compared to control training. However, no significant improvement in sport-specific performance was found (SMD = 0.11, 95% CI [-0.18, 0.40], p = 0.46). Substantial heterogeneity was observed for strength outcomes (I2 = 75%), whereas low heterogeneity was observed for sport-specific performance and hypertrophy outcomes (I2 = 0%). No evidence of significant publication bias was detected. CONCLUSION: BFRT combined with RT appears to provide effective augmentation of lower-limb muscle strength and hypertrophy in athletes compared to RT or conventional training alone. It may be prudent to integrate this approach systematically into training cycles to optimize physiological muscle stimulation and training outcomes, despite not directly improving sport-specific performance.

Humans↗

PubMedDate not supplied

Kinesiologic measurements of functional performance before and after geometric total knee replacemtn: one-year follow-up of twenty cases.

Kinesiologic measurements were made in patients with severe arthritis before and after geometric total knee replacements to evaluate the nature, rate and extent of change in their functional ability. Preoperatively, patients with rheumatoid arthritis functioned at lower levels than patients with osteoarthritis. Most patients with rheumatoid arthritis improved steadily after surgery, while progress of those with osteoarthritis was often irregular. The group with rheumatoid arthritis improved more than those with osteoarthritis, but they did not generally reach the functional level attained by the patients with osteoarthritis, and neither group reached the lower limits of normal variability 1 year postoperatively. On the average, both groups gained knee extensions, lost knee flexion, and gained isometric knee flexor muscle strength postoperatively. Every patient with osteoarthritis lost extensor muscle strength 1 year after surgery, while most with rheumatoid arthritis gained. During quiet standing, most patients had straighter knees postoperatively and bore a greater percent of body weight on the operated limb. Patients with rheumatoid arthritis improved more than patients with osteoarthritis in the type and amount of force applied to canes and crutches. Most patients walked faster postoperatively, took longer and more rapid steps, improved the pattern of knee motion used, and had smoother forward, lateral and vertical head motion.

Aged↗

PubMed2026

Effects of different resistance exercise programs on upper limb functional recovery in postoperative breast cancer patients.

PURPOSE: To investigate the effects of grip strength exercise combined with upper limb resistance exercise on upper limb functional rehabilitation in patients after breast cancer surgery. METHODS: A total of 111 patients who underwent either modified radical mastectomy with ALND or breast-conserving surgery with ALND were randomly assigned to a control group, an upper limb resistance exercise group, and a combined grip and upper limb resistance exercise group. Grip strength was measured at baseline, 16 weeks after intervention, and at 3- and 6-month follow-ups, while shoulder function was assessed using the Constant-Murley Scale (CMS). RESULTS: There were no statistically significant differences in grip strength or CMS scores among the groups before intervention (P > 0.05). At the post-intervention, 3-month, and 6-month follow-ups, compared with the control group, both resistance training protocols significantly improved patients' joint range of motion, pain, muscle strength, total CMS score, and grip strength (P < 0.05). Compared with the upper limb resistance exercise group, the combined grip and upper limb resistance exercise group demonstrated superior grip strength at the 6-month follow-up (P < 0.05), as well as more significant improvements in joint range of motion, pain, muscle strength, and total CMS scores (P < 0.05). CONCLUSION: A 16-week resistance exercise program effectively improves upper limb function in post-surgical breast cancer patients, with the combined grip and upper limb resistance exercise program yielding superior outcomes.

Humans↗

PubMed2026

The Effect of Game-Based Virtual Reality Rehabilitation and Its Impact on Upper Extremity Function After Arthroscopic Rotator Cuff Repair: A Randomized Controlled Trial.

BACKGROUND: Arthroscopic rotator cuff repair (ARCR) often results in prolonged recovery and limited shoulder function. Conventional physical therapy rehabilitation programs require sustained patient engagement; however, adherence is frequently low. Game-based virtual reality (VR) offers an interactive and engaging environment that may enhance rehabilitation outcomes. OBJECTIVE: To evaluate the effect of a game-based VR program on the function of the upper limb in patients following ARCR. METHODS: A randomized controlled trial was conducted with patients who underwent ARCR. Participants were randomized into two groups: game-based VR or conventional rehabilitation. Outcomes were evaluated using the Disabilities of the Arm, Shoulder and Hand score, pain severity by the Numerical Pain Rating Scale, range of motion measures, and muscle strength testing. Assessments were performed at baseline and at 6 weeks and 12 weeks post surgery. RESULTS: Results have shown significant within-group improvements in pain, function, range of motion, and isometric muscle strength across all time points (P < 0.05). Between-group analysis revealed greater improvements in pain, function, flexion range, and abduction and external rotation strength in the experimental group at both time points (P < 0.05). Abduction range improved significantly only at 12 weeks (P = 0.02), whereas external rotation range showed no significant difference between groups at either time point (P > 0.05). CONCLUSION: The findings indicate that integrating game-based VR rehabilitation provides additional benefits over conventional therapy in improving pain and upper extremity function following ARCR. These findings support the use of VR as an effective alternative to the conventional rehabilitation for postoperative rehabilitation.

Humans↗

PubMed2025

Mechanism of Qigu capsule as a treatment for sarcopenia based on network pharmacology and experimental validation.

OBJECTIVE: To explore the potential molecular mechanism of Qigu capsule (，QGC) in the treatment of sarcopenia through network pharmacology and to verify it experimentally. METHODS: The active compounds of QGC and common targets between QGC and sarcopenia were screened from databases. Then the herbs-compounds-targets network, and protein-protein interaction (PPI) network was constructed. Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis were performed by R software. Next, we used a dexamethasone-induced sarcopenia mouse model to evaluate the anti-sarcopenic mechanism of QGC. RESULTS: A total of 57 common targets of QGC and sarcopenia were obtained. Based on the enrichment analysis of GO and KEGG, we took the phosphatidylinositol 3-kinase (PI3K)/protein kinase B (Akt) signaling pathway as a key target to explore the mechanism of QGC on sarcopenia. Animal experiments showed that QGC could increase muscle strength and inhibit muscle fiber atrophy. In the model group, the expression of muscle ring finger-1 and Atrogin-1 were increased, while myosin heavy chain was decreased, QGC treatment reversed these changes. Moreover, compared with the model group, the expressions of p-PI3K, p-Akt, p-mammalian target of rapamycin and p-Forkhead box O3 in the QGC group were all upregulated. CONCLUSION: QGC exerts an anti-sarcopenic effect by activating PI3K/Akt signaling pathway to regulate skeletal muscle protein metabolism.

Sarcopenia↗

PubMed1976

Action of dantrolene sodium in spasticity with low dependence on fusimotor drive.

The effects of dantrolene sodium, an anti-spasticity drug with a site of action within the muscle fibres, were studied in 19 patients with spastic paresis. Oral doses were successively increased from 100 mg/day to a maximal tolerated level or up to 800 mg/day. Trial periods were 8-13 weeks. The responses of stretch reflexes to local cooling over the spastic muscles were used to differentiate alpha and gamma spasticity. In the knee extensor and flexor muscle groups, cryo-negative alpha-spasticity was seen in 25 and cryo-positive gamma-spasticity in 4 muscle groups. Ankle clonus was cryo-positive in 14 of 15 cases. Resistance to passive knee joint movements, ankle clonus and isometric or isokinetic muscle strength was determined quantitatively. The gait was recorded by intermittent-light photography and the muscle activation patterns in gait were studied in recordings of the average EMG from limb muscles. Functional disability and spasms were assessed from clinical examinations and interviews. Passive resistance at slow (6%/sec) and fast (30 degrees/sec) knee joint movements decreased by 32% in the extensor muscles (p = 0.005 resp. 0.001) and by 23-26% in the flexor muscles (not significant). Reduced passive resistance was observed in 16 of the muscles with alpha-spasticity and in all 4 of the muscle groups with gamma-spasticity. Clonus was diminished or abolished in 14 of 15 patients with this sign. Maximal isometric or isokinetic muscle strength was unaltered in the majority of the patients. In a few the strength was increased, in some it was decreased. The averaged EMG activity during walking as studied in 10 patients were increased in 35 of the 57 muscle groups examined. In some muscle groups, exaggerated activity attributable to spastic reflexes was reduced. Motor disability was decreased significantly in 10 patients. It was not significantly changed in 5 and deteriorated in 4 patients. Drowsiness and subjective muscle weakness were the most frequent side-effects. SGOT and SGPT were increased in 3 cases.

Adult↗

PubMed1979

Relationship of static respiratory muscle pressure and maximum voluntary ventilation in normal subjects.

40 normal subjects performed spirometry, maximum voluntary ventilation (MVV), and tests of static inspiratory (Pi max) and expiratory (Pe max) respiratory muscle pressure. Forced expiratory volumes in 0.5 (FEV0.5), in 0.75 (FEV0.75), and 1 sec (FEV1) correlated significantly with MVV (r = 0.805, 0.804, 0.779, respectively). When Pi max was considered as a second independent variable, the probability of predicting MVV from timed forced expiratory volumes was enhanced (r = 0.914, 0.900 and 0.872 for FEV0.5, FEV0.75, and FEV1, respectively). Statistical analysis indicated that multiple regression with Pi max was superior to regression with timed forced expiratory volume alone in the prediction of MVV. For any given FEV1, however, Pi max was widely dispersed (range: -60 to -200 cm H2O). MVV values, expressed as percentage difference between largest and smallest value, varied less than did Pi max. Pe max, vital capacity, height and age did not enhance the ability of timed forced expiratory volumes to predict MVV. These data indicate that while respiratory muscle strength is important for sustaining maximal ventilation, the MVV is not a sensitive indicator of respiratory muscle strength.

Adult↗

PubMed2026

Ghrelin Receptor Deletion or Pharmacological Inhibition Improves Muscle Function in Aging Male Mice.

Sarcopenia is characterized by age-related declines in muscle strength and mass, along with impaired physical function. It remains an unmet medical need, and there are no pharmacological interventions approved for this indication. The activation of growth hormone secretagogue receptor (GHSR)-1a, also known as ghrelin receptor, stimulates food intake and has acute anabolic effects. However, its impact on aging muscles remains uncertain. We examined the effects of GHSR-1a deletion on sarcopenia measurements (muscle mass, strength, and endurance) by comparing young and aged male GHSR-1a knockout (KO) and wildtype (WT) mice (6-, 24-, and 28-month-old). Deletion of GHSR-1a improved muscle fatigue resistance, endurance, and muscle strength during aging without affecting muscle mass or longevity. Since muscle endurance is closely related to mitochondrial function, we examined mitochondrial biogenesis marker PGC-1α and mitophagy signaling via PINK1/p62 and found them improved in old mice with GHSR deletion. Proteomics analysis also revealed that mitochondrial components remain central for maintaining muscle mass and function. We further investigated the effects of pharmacological inhibition of GHSR-1a by its inverse agonist, PF-5190457, in male WT mice. PF-5190457 mimicked the effects of GHSR-1a deletion, including improved endurance and increased markers of mitochondrial biogenesis (PGC-1α) and different mitophagy markers (LC3II and Bnip3). PF-5190457 also reduced body weight and adiposity, which were not observed with GHSR-1a deletion. Overall, these findings suggest that GHSR-1a is a promising therapeutic target for age-related sarcopenia.

Receptors, Ghrelin↗

PubMed2026

Using the OPTIMAL Theory to Optimize Aerodynamics in Respiratory Training for Healthy Adults and Individuals With Parkinson's Disease.

BACKGROUND: The OPTIMAL (Optimizing Performance Through Intrinsic Motivation and Attention for Learning) theory is a motor learning framework proposing that optimizing intrinsic motivation enhances motor performance and learning. The theory identifies three key components-Enhanced Expectancies (EE), Autonomy Support (AS) and External Focus of Attention (EF)-which facilitate more efficient, goal-directed movement. These components have been shown to improve motor outcomes in limb-based tasks; however, their application to respiratory training, particularly in clinical contexts such as voice and swallowing therapy in patients with Parkinson's disease (pwPD), has not yet been systematically explored. AIMS: This study aimed to investigate whether implementing OPTIMAL theory strategies during a respiratory muscle strength training (RMST) task improves immediate respiratory motor performance in healthy adults and pwPD. Additionally, we aimed to examine the effects of these strategies on motivation and cognitive engagement. METHODS: This quasi-randomized, single-session trial included 47 participants: Healthy CONTROL (n = 17), Healthy OPTIMAL (n = 16) and PD OPTIMAL (n = 14). Healthy participants were quasi-randomly assigned to either intervention or control conditions, whereas pwPD completed the intervention only. All participants completed a single respiratory session that included baseline, practice and retention phases. Outcome measures included peak expiratory flow, cough peak expiratory flow, cognitive engagement (EEG-based Cognitive Engagement Index) and self-administered motivation questionnaire. OUTCOMES AND RESULTS: Exhalation force improved from baseline to retention in the Healthy OPTIMAL group (baseline: M = 296 L/min; retention: M = 338 L/min; p < 0.001) and the PD OPTIMAL group (baseline: M = 315 L/min; retention: M = 370 L/min; p < 0.0001), but not in the Healthy CONTROL group (p > 0.05). No significant changes in cough strength were observed in any group. No correlations were found between cognitive engagement and exhalation force or motivation scores. However, motivation increased more in the Healthy OPTIMAL group (Questionnaire 1: M = 57.2; Questionnaire 2: M = 60.7) and the PD OPTIMAL group (Questionnaire 1: M = 60.1; Questionnaire 2: M = 62.8) than in the Healthy CONTROL group (Questionnaire 1: M = 61.1; Questionnaire 2: M = 62.5). CONCLUSIONS AND IMPLICATIONS: Implementing the OPTIMAL theory enhances immediate respiratory motor performance in both healthy participants and pwPD. OPTIMAL theory has clinical value in voice and swallowing therapy, although further research is needed to establish long-term efficacy and clinical impact. WHAT THIS PAPER ADDS: What is already known on the subject Motivation is a critical factor in rehabilitation. The OPTIMAL theory has been shown to improve both motivation and motor performance in limb-based tasks. Its impact on respiratory training, however, has not been previously examined. What this paper adds to the existing knowledge This study shows that applying OPTIMAL strategies during a respiratory muscle strength training task significantly improved peak expiratory flow in both healthy adults and people with Parkinson's disease. What are the potential or clinical implications of this work? Integrating the OPTIMAL theory principles into respiratory therapy may enhance motor outcomes, supporting voice, swallowing and cough rehabilitation.

Humans↗

PubMed2026

Characterizing Submental Neuromuscular Activity of Swallowing Rehabilitation: An Electromyographic Evaluation of Rehabilitative Maneuvers in Healthy Adults.

PURPOSE: The effortful swallow (ES), the Mendelsohn maneuver (MM), and isometric tongue presses (TPs) are widely used swallowing maneuvers/exercises to improve elements of swallowing, such as muscle strength and biomechanics. However, the underlying neuromuscular mechanisms of these exercises remain unclear, potentially limiting our ability to specify treatment targets and improve treatment efficacy. This study aimed to compare submental neuromuscular activation patterns during the ES, MM, TPs, and typical swallows in healthy young and older adults. METHOD: As part of a larger randomized crossover validation study, 60 healthy adults (30 young and 30 older) completed typical swallows and three maneuvers using a wearable submental surface electromyographic (sEMG) system (i-Phagia). Outcome variables included (a) normalized mean sEMG amplitude and (b) time to peak sEMG amplitude. Linear mixed models were used to examine effects of task, age, and sex on both outcomes. RESULTS: Normalized mean amplitude was significantly different across tasks. Post hoc pairwise comparisons confirmed that all three maneuvers produced higher normalized mean sEMG amplitude than typical swallows, with the ES eliciting the highest amplitude across age groups. Time to peak amplitude differed significantly across tasks, with typical swallows requiring the shortest time to reach peak amplitude, followed by the ES, MM, and TP. CONCLUSIONS: The ES required the highest neuromuscular effort with the shortest time to reach peak amplitude, suggesting its potential for targeting submental muscle power. Typical swallows required the least neuromuscular effort with the shortest time to reach peak amplitude, suggesting their potential for training submental muscle speed. The MM and TP may also improve submental muscle strength; however, given their temporal requirements (longer durations), they may be more beneficial for targeting coordination and endurance, though more research in this area is warranted. These findings underscore the importance of task-specific neuromuscular profiling to inform mechanism-based swallowing rehabilitation. SUPPLEMENTAL MATERIAL: https://doi.org/10.23641/asha.32948549.

Humans↗

PubMed2025

Lysine-rich rice enhanced muscle growth and development in young rats.

Rice is the staple food for half of the world's population but is low in lysine content. We previously developed transgenic lysine-rich rice with enhanced free lysine content in rice seeds and demonstrated that it could improve skeletal growth and development in rats. However, the effects of lysine-rich rice on muscle remain to be studied. We hypothesized that lysine-rich rice was able to improve muscle growth in weaning rats via its anabolic effects on muscle metabolism. Male weaning Sprague-Dawley rats received lysine-rich rice (HFL) diet, wild-type rice (WT) diet, or wild-type rice with various doses of lysine supplementation (WT + Lys) diet (+ 0%, + 10%, + 20%, and + 40% lysine) for 70 days. Muscle strength and quality were analyzed by biomechanical test and muscle fiber typing of the extensor digitorum longus (EDL) muscles. Molecular mechanisms of lysine on muscle growth were also explored by rat serum biochemistry and cell culture systems. Results indicated that the HFL diet improved rats' muscle growth, strength, and physiological cross-sectional area (CSA) over the WT diet group. The CSAs of fast-twitch muscle fibers (Type IIb and IIx) were also increased. In addition, the HFL increased serum insulin-like growth factor 1 (IGF-1) and decreased serum myostatin (MSTN) concentrations. The cell culture model showed that lysine deficiency reduced IGF-1 expression and inhibited myoblast differentiation associated with muscle growth. Our findings showed that lysine-rich rice improved muscle growth and development in weaning rats. Higher dietary lysine possibly inhibited MSTN and activated of IGF-1 signaling pathway for muscle growth and development.

Animals↗

PubMed1976

Shoulder muscle tenderness and physical features of female industrial workers.

Physique, muscle strength, and jump-step scores of female industrial workers, ages 17--34, were studied in relation to tenderness of shoulder muscles for five groups, (A) character display operators, (B) fluorescent lamp assemblers, (C) photographic film rolling workers, (D) teachers and nurses of handicapped children, and (E) office workers. No significant differences were found between the five groups in mean body height, body weight, and skinfold thickness, but mean knee extension force of groups A and C and mean back muscle strength of groups A, B, and C was significantly lower than that of group E. Workers of groups C and D with a low tenderness threshold of m. trapezius of 0.6 kg/cm2 or less had stiff shoulders more frequently and lower force levels of knee extension, back muscle, and upper arm abduction than those without tenderness. No similar tendency was found for groups B and E. Further, among workers with objective signs of occupational cervicobrachial disorder, there were few whose knee extension force or jump-step scores were above the averages of normal office workers. Shoulder muscles of such operators were revealed to be continuously contracted during operations. The possible effects of chronic fatigue due to repetitive operations on developing localized tenderness and occupational hazards are discussed.

Adolescent↗